<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        function Tom() {
            getName = function () {
                alert(1);
            }
            return this;

        }
        Tom.getName = function () {
            alert(2);
        }

        Tom.prototype.getName = function () {
            alert(3);
        }
        var getName = function () {
            alert(4);
        }

        function getName() {
            alert(5)
        }


        Tom.getName();
        getName();
        Tom().getName();
        getName();
        new Tom.getName();
        new Tom().getName();
        new new Foo().getName();
    </script>
</body>

</html>